Crash with ArrowFunctionExpression as ExpressionStatement

[Conduitry]

cr.print(cr.b`() => {}`).code

throws

Uncaught TypeError: Cannot read property 'type' of undefined
    at ExpressionStatement (.../code-red/dist/code-red.js:341:49)
    at handle (.../code-red/dist/code-red.js:71:18)
    at .../code-red/dist/code-red.js:249:19
    at Array.map (<anonymous>)
    at handle_body (.../code-red/dist/code-red.js:248:22)
    at Program (.../code-red/dist/code-red.js:319:11)
    at handle (.../code-red/dist/code-red.js:71:18)
    at print (.../code-red/dist/code-red.js:1414:18)
    at Object.print (.../code-red/dist/code-red.js:1399:11)

There's apparently an extra situation that needs to be handled here now that ArrowFunctionExpression has precedence 3.

Ref. sveltejs/svelte#4617

[Conduitry]

Looking at this quickly, there's no reason as far as I can tell to be checking for the precedence of the operator, rather than just checking for the type of the node. So I think we could instead do node.expression.type === 'AssignmentExpression' && node.expression.left.type === 'ObjectPattern'.